Patterson-UTI reports drilling activity for December 2013

Patterson-UTI Energy, Inc. reported that for the month of December 2013, the Company had an average of 187 drilling rigs operating in the United States and 9 rigs in Canada. For the three months ended December 31, 2013, the Company had an average of 183 drilling rigs operating in the United States and 9 rigs in Canada.

Average drilling rigs operating reported in the Company's monthly announcements represent the average number of the Company's drilling rigs that were operating under a drilling contract. The Company cautioned that numerous factors in addition to average drilling rigs operating can impact the Company's operating results and that a particular trend in the number of drilling rigs operating may or may not indicate a trend in or be indicative of the Company's financial performance. The Company intends to continue providing monthly updates on drilling rigs operating shortly after the end of each month.